Centrifugal separator



Feb. 12, 1952 H. R. DRURY 2,585,753

CENTRIFUGAL SEPARAT'OR Filed Nov. so, 1948 2 SHEETSSHEET 1 1/ INVEN TOR.

Feb. 12, 1952 H. R. DRURY CENTRIFUCAL SEPARATOR 2 SHEETS-SHEET 2 FiledNov. 30, 1948 INVEN TOR.

HE/QBE/QT Del/RY A TTOE/VE) black sand or magnetite.

The top wall of the pocket comprises a horizontal portion 42 and anupwardly inclined portion 43. The upper wall of the pocket extendsinwardly beyond the upper edge of the bowl and terminates in anoutwardly curved discharge flange 44 of substantial width which extendshorizontally beyond the outer extremity of the side wall of the pocket36 and serves to direct and greatly stimulate the movement of tailingsfrom the bowl. The top wall of the pocket defines a discharge openingfor the bowl ofjsmaller diameter than the maximum diameter of the bowl.The form and position of the concentrating pocket of the device isimportant in carrying out the objects of this invention in that bothcentrifugal force and gravity are employed to concentrate thevaluablemetal or mineral which is collected in its outer andlower'diameter in the presence of The amount'of black sand or magnetitecollected in the pocket is substantially limited due to the shape of theupper part of the pocket and the reduced diameter of the pocket at thatpoint. the residue or tailings of sand, gravel, water and black sandbeing drawn up and outward by the centrifugal force and speedilydischarged by the discharge flange 44.

In order to protect the inner surface of the bowl a renewable bowl liner45 preferably molded from rubber. or a suitable plastic is provided.Such a liner will greatly outwear the metallic bowl, can be economicallyreplaced when worn out and serves to reduce the weight of the device.Drain plugs 46 are provided in the base of the bowl through which theconcentrate may be removed from the bowl from time to time.

A circular launder 41 is coaxially positioned about the rim of the.discharge flange 44 of the bowl. The launder'41 includes an outercylindrical wall 48, an inner cylindrical wall 49 and a. fiat inclinedbottom 50 thus forming anasymmetrical annular chamber. A rectangulardischarge chute is provided adjacent the lower portion of the bottom 50.The walls, bottom and chute are suitably secured together as by weldingto form a completed unit. The launder is supported by a plurality ofangle brackets 52 bolted or otherwise secured to members 53 extendingupwardly from the base IIL.

The bowl I1 is fed from a feed chute 54 which opens to the interior ofthe bowl adjacent the bottom thereof. A suitable bracket55 supported bythe members 53 serves to maintain the chute 54 in proper position withinthe bowl.

With reference to Figures 3 and 4 of the drawings, there is illustratedan attachment 5'! which positioned at spaced points about the pocket andare adapted to rotatetherewith and will be re- 4 ferred to hereinafteras accelerators. The accelerator 51 comprises a plate 58 adapted to besecured to the wall portion 43 of the pocket 35 by means of bolts 59.The plate 58 has angularly secured thereto an impeller 60. The impelleris preferably disposed at an angle of forty-five degrees to the axis ofrotation of the bowl when mounted therein and when so positioned servesto act on the water and gravel passing the mouth of the concentratingpocket to direct it upwardly and outwardly onto the discharge flange 44whereby it is conveyed to the launder 41.

Where there is a great amount of black sand or magnetite present in theplacer sand, gravel or mine tailings, the accelerators are provided witha flow directing finger 6| welded or otherwise secured to the outer endof each impeller and extending downwardly and outwardly toward theconcentrating pocket. The finger extends preferably at an angle offorty-five degrees to the radius of the bowl at'that point and the fiatside of the finger is inclined at an angle of forty-five degrees to thedirection of rotation. The finger serves to interrupt the upward flow ofmaterial along the inner surface of the bowl, agitate the same anddirect it into the mouth of the pocket.

In using the device the gangue or conglomeration of various metallicsubstances and associated substances, preferably in a finely divi'ded'state and mixed with sumcient water to form 'a pulp is introduced intothe bowl I! through the feed chute 54 and deposited in the bottom of thebowl. The bowl is then rotated so as to cause the mix ture to traveloutwardly and upwardly over the interior surface of the liner 45. I havefound that where a bowl with a diameter of thirty-six inches is used aspeed of about one hundred eighty R. P. M. is preferable. Therotation ofthe bowl creates a centrifugal force which acts upon the mixture and itscontained solids as it moves upwardly along the smooth interior surfaceof the bowl causing the heavy desirable min eral particles to be forcedfurther outwardly than the lighter particles thereby becoming classified as the mixture reaches the pocket. Due to the smooth surface of thebowl the contents never reaches the speed of the bowl, there beingconsiderable slippage between the contents and the wall of the bowl. Ihave found that the contents of the bowl reaches its maximum rotativespeed at a point adjacent the mouth of the concentrating pocket which isabout two-thirds as great as the speed of the bowl. The accelerators 51located at spaced points around the bowl immediately above the pocketrevolve at a speed greater than the speed of the contents, thus creatinga positive action upon the rising contents of the bowl by first creatinga secondary flow of the contents into the pocket in addition to theaction of centrifugal force and then creat ing an accelerated movementof the'contents up} wardly after passing the pocket, and thus clearingaway any excess substance from the pocket where it is picked up byflange 44 and directed out of the bowl into the launder. The foregoingaction continues until a considerable amount of concentrate hasaccumulated in the pocket; at which time the feed of solid'substanceisfirst stopped, and then the flow of water is cut off. leaving the bowlclean but with the concentrate of heavy metal and some sand and blacksand in the pocket. The rotation of the bowl is stopped and the pocketwashed out-anddrained into a suitable receptacle through the:drain-plugs =46. Having thus described my invention, sothat thoseskilled in the art may practice the same, what I desire to obtain byLetters Patent is defined in the appended claims.

I claim:

1. A centrifugal separator comprising a substantially hemispherical bowlhaving a smooth renewable liner, means for rotating said bowl about avertical axis, a circumferential concentrating pocket mounted on the rimof said bowl and opening inwardly thereof, said pocket having upper andlower horizontal walls and a circumferential wall positioned outwardlyof the rim of the bowl, the upper wall extending inwardly of the rim ofthe bowl, and a plurality of accelerators mounted on the inner extremityoi the upper wall of said pocket and positioned adjacent the mouth ofthe pocket, said accelerators having a portion extending downwardly andoutwardly toward the mouth of the pocket whereby material movingupwardly along the internal wall of said bowl will be interrupted anddirected into said pocket.

2. A centrifugal separator comprising a substantially hemispherical bowlhaving a smooth renewable liner, means for rotating said bowl about avertical axis, a circumferential concentrating pocket mounted on the rimof said bowl and opening inwardly thereof, said pocket having upper andlower horizontal walls connected by a circumferential wall positionedoutwardly of the rim of the bowl, and a plurality of acceleratorsmounted on the upper wall of said pocket inwardly of the inner surfaceof the rim of the bowl and positioned adjacent the mouth of the pocket,said accelerators having one portion extending downwardly and outwardlytoward the mouth of the pocket whereby material moving upwardly alongthe internal wall of said bowl will be interrupted and directed intosaid pocket and a second portion extending inwardly and downwardly andserving to direct material passing from the mouth of the pocket on tosaid discharge flange.

3. A centrifugal separator comprising a substantially hemispherical bowlhaving an outwardly extending flange formed on the rim thereof, meansfor rotating said bowl about a vertical axis, a concentrating pocketmounted on the flange of said bowl, said pocket being formed with acircumferential wall spaced outwardly beyond the rim of said bowl and awall spaced from said flange extending perpendicular to the axis ofrotation of the bowl from said circumferential wall to a point spacedinwardly of the upper edge of the bowl and terminating in a reverselyextending discharge flange, and a plurality of accelerators mounted onthe inner extremity of said wall of said pocket and positioned adjacentthe mouth of said pocket, said accelerators having one portion extendingdownwardly and outwardly toward the mouth of the pocket whereby materialmoving upwardly along the internal wall of said bowl will be interruptedand directed into said pocket.

4. A centrifugal separator comprising a substantially hemispherical bowlhaving a smooth renewable liner, means for rotating said bowl about aVertical axis, a concentrating pocket mounted on the flange of saidbowl, said pocket having a circumferential wall spaced outwardly beyondthe rim of said bowl and a horizontal wall spaced from said flangeprojecting inwardly of the upper edge of the bowl and terminating in areversely extending discharge flange, and a plurality of acceleratorscarried by said pocket and positioned adjacent the mouth thereof, saidaccelerators having one portion extending downwardly and outwardlytoward the mouth of the pocket whereby material moving upwardly alongthe internal Wall of said bowl will be interrupted and directed intosaid pocket, and a second portion extending inwardly and downwardly andserving to direct material passing from the mouth of the pocket on tosaid discharge flange.

HERBERT R. DRURY.

REFERENCES CITED The following references are of record in the flle ofthis patent:

UNITED STATES PATENTS Number Name Date 444,613 Peck Jan. 13, 1891528,735 Naylor Nov. 6, 1892 604,978 Garland May 31, 1898 808,584 X. St.Pierre Dec. 26, 1905 1,708,970 Kleinschmidt Apr. 16, 1929 1,853,249Ainlay Apr. 12, 1932 1,947,844 Gish Feb. 20, 1934 1,988,528 Waltman Jan.22, 1935 1,997,971 Lindberg a Apr. 16, 1935 2,272,675 Knudsen Feb. 10,1942

